topic HP DL380-G5 - RAID 0 Question in ProLiant Servers (ML,DL,SL)

HP DL380-G5 - RAID 0 Question

Steve Trickey — Thu, 18 Oct 2007 10:41:33 GMT

I want to expand the server now so that it has an additional form of redundency, currently it is running Raid 0.

What I would like to know is, is it possible once I have added 4 more drives to alter the Raid 0 to either 1+0 or 5 without affecting the data already in place?

Thanks
Steve

Re: HP DL380-G5 - RAID 0 Question

James ~ Happy Dude — Thu, 18 Oct 2007 12:39:14 GMT

No Steve,
Thats not possible; While converting from RAID 0 to ANY other RAID level WILL have to go through a data cleaning;
Please Back up your data, before you jump RAID level;

I dont consider RAID 0 as "RAID" by definition;
"Redundant Array of Independent Drives" > There is NOTHING redundant in RAID 0;

Regards,
James.

Re: HP DL380-G5 - RAID 0 Question

KarloChacon — Thu, 18 Oct 2007 22:40:38 GMT

hi Steve

what is controller that you have?
you know some controllers have the option to migrate a RAID Levels, for example P400 does not have the option until you add 512 BBWC... long history

I've searching and I think that's possible of course if you have smart array controller

what you need to do is add new HDDs extend the logical drive and migrate to RAID 5

check these threads
http://urlao.com/migrate1
http://urlao.com/migrate2
http://urlao.com/migrate3

regards

Re: HP DL380-G5 - RAID 0 Question

KarloChacon — Thu, 18 Oct 2007 22:49:04 GMT

hi again

maybe you have e200 or p400 both have the option for online migration raid level
P400
http://h18000.www1.hp.com/products/quickspecs/12400_div/12400_div.HTML

e200 - e200i
http://h18000.www1.hp.com/products/quickspecs/12460_div/12460_div.HTML

both
** Online RAID level migration (with BBWC upgrade)

so you can migrate your RAID 0 to RAID 5

so when you do this the RAID 0 is going to stripe the data along the new HDDs and calculate the parity for the RAID 5

regards

Re: HP DL380-G5 - RAID 0 Question

e4services — Fri, 19 Oct 2007 09:34:41 GMT

Steve, Karlo is correct. The restriction on being able to actively (online) migrate RAID levels is having to do with the installation of the cache, for without it the action is not possible. The cache can be added to most controllers if it is not installed.
OR, you always have the option of simply adding the RAID 5 and moving your data to it, leaving the OS on the single drive, which is preferred anyway, because having a redundent OS doesn't server much purpose and it eats up SO much of the RAID controllers resources with all its reads and writes all the time. This takes some work relocating the data locations for what ever software you have, but it can be done. Exchange even has a function to do such a thing. Then simply back up the OS drive. (a ghost to an external drive or a temporary internal drive is an elegant solution cause all you are worried about is something corrupted your OS)
OR simply backup and restore when the server is offline also has no restriction in the RAID contoller.

Re: HP DL380-G5 - RAID 0 Question

Steve Trickey — Fri, 19 Oct 2007 12:10:53 GMT

Thanks guys, I'l do some reading before starting anything :)

I have the Smart Array P400 with 256mb and the cache is enabled, and although I don't have the migrate options showing yet I'd have a safe guess it is because the sas disks are not in place yet.

It's a system I have inherited and in my own setups I like to have backup but there was none in this and I've nvr done raid swaps before..

Thanks again :)

Re: HP DL380-G5 - RAID 0 Question

Steve Trickey — Fri, 19 Oct 2007 12:17:35 GMT

DOH! And of course the missing 512 bbwc will help to show the options..

One of those days....

TY again.

Re: HP DL380-G5 - RAID 0 Question

1t1nl0 — Sat, 20 Oct 2007 19:42:13 GMT

Hello Steve,

All this is possible as long as you have a Smart Array controller with the battery-backed write cache (BBWC).

I suggest you check out the ACU manual for this:
http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00729544/c00729544.pdf

First you'll need to use the ACU to expand the existing array (page 16) to contain these new disks.

Once this is done, you'll need to proceed with a RAID migration (page 17) which takes quite some time.

Either way, a backup of your data is strongly recommended since any problem during the process could end with data loss or corruption.

Regards,
- Agus